The invention relates to a guard tube assembly with a guard tube and an inner support tube for supporting a drive shaft of a hand-guided power tool, wherein the drive shaft and the support tube are extending in longitudinal direction of the guard tube assembly and the support tube has a central bearing sleeve. The bearing sleeve carries elastic support elements and the bearing sleeve is supported by the elastic support elements on the inner contour of the guard tube.
U.S. Pat. No. 4,953,294 discloses a support tube (liner) comprising a bearing sleeve held by means of radial supporting ribs in a protective tube that is cylindrical across its entire length. The support tube is supposed to ensure a vibration-free, wear-resistant support of the drive shaft in the protective tube wherein the drive shaft connects a drive with a rotary tool member. Such a drive connection can operate at rotary speeds of up to 10,000 rpm. A problem in this connection is rotary entrainment of the support tube; for this reason, this patent proposes that at least one supporting rib is to be designed springy in order to achieve a clamping fixation of the support tube in the cylindrical guard tube.
The invention has the object to support a drive shaft which is guided in a guard tube by means of a support tube in such a way that rotary entrainment of the support tube is reliably prevented.